Reclosure adhesive layered articles, also known as sealing labels, are one typical adhesive functional application which requires performance characteristics that enable the sealing label to be removed and resealed to the packaging, for example, from 1 to 150 times. Typically, the number of items contained in a package correlates to the number of times reclosure is required. If a single use/serving product is provided in a package, then the resealing capabilities of a layered article may only need to provide 1 to 3 reclosures. This situation is illustrative of resealable containers for dry pasta, bread, candy, or the like. Other situations may require a greater number of reclosures, i.e. 10 to 20 reclosures or even 50 to 150 reclosures. Examples of these are travel tissue containers, frozen vegetable containers, sliced meat containers, and the like.
The adhesive used to reseal a layered article to a container must have a certain level of resistance to degradation from the product in the container. This level of resistance to the package contents must increase as the number of required reclosures increases because the adhesive is presumably in proximity to the contents for a longer period of time. This increase in product resistance of the adhesive ensures proper reclosures of the container and prevents loss of adhesion. Loss of adhesion could cause product contamination, product degradation, or exposure to environmental elements.
Of particular importance is the resealing capability of layered articles that seal containers for “wet” products. By “wet” it is meant a product that contains an amount of moisture (being water, alcohol, or other liquid medium) that may decrease the adhesion of the layered article to the container, such as wet tissue or wet wipes. Wet products are one of the most challenging applications in the reclosure market because they can reduce the bond strength of an adhesive. Good content resistance is necessary for wet sealing layered articles because normally, about 50 to about 150 reclosures are required.
Typical wet sealing labels comprise a film facestock, a reclosure adhesive, and a release liner for production and handling purposes. The above structure has adequate performance for wet products that are free of alcohol content. But for wet product with high concentrations of alcohol, this type of reclosure adhesive has poor alcohol resistance and therefore has poor resealing capabilities. The bonding strength of the typical sealing label will decrease due to alcohol corrosion to the adhesive. Furthermore, as a result of alcohol evaporation, the functional component in the content formulation of the adhesive could migrate away from the layered article and package interface.
Problems associated with typical sealing labels, as applied to high alcohol content wet product, can lead to an improper seal that fails to maintain the integrity of the packaging. Over time, an improper seal can cause degradation of the high alcohol content wet product. Degradation can include evaporation of the liquid component of the product which produces a dry item not suitable for its intended purpose.
Therefore, a need exists to have a layered article that provides proper adhesion for high alcohol content wet products.